SOLUTION: A man bought 4 pounds of coffee and 1 pound of butter for a total of $22.25. A month later, the prices had not changed and he bought 5 pounds of coffee and 4 pounds of butter for $

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Question 892760: A man bought 4 pounds of coffee and 1 pound of butter for a total of $22.25. A month later, the prices had not changed and he bought 5 pounds of coffee and 4 pounds of butter for $34.00. Find the price per pound of both coffee and butter.
Answer by LinnW(1048) About Me  (Show Source):
You can put this solution on YOUR website!
let c = price of a pound of coffee
b = price of a pound of butter
four times the price of one pound of coffee plus 1 times the price
of a pound of butter equals $22.25
4*c + 1*b = $22.25
five times the price of one pound of coffe plus four times the price
of a pound of butter equals $34.00
5*c + 4*b = $34.00
Here are the two equations.
4c + b = 22.25
5c + 4b = 34.00
multiply the top equation by -4
-16c -4b = -89
5c +4b = 34
add the equations
-11c = -55
divide by -11
c = 5
substitute 5 for c in 5c + 4b = 34
5(5) + 4b = 34
25 + 4b = 34
add -25 to each side
4b = 9
divide by 4
b = 9/4 = 2.25
Coffee is $5 per pound and butter is $2.25 per pound